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1.
PLoS One ; 19(5): e0295088, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38776332

RESUMO

Yaws affects children in tropical regions, while syphilis primarily affects sexually active adults worldwide. Despite various campaigns towards the eradication of yaws and elimination of syphilis, these two diseases are still present in Ghana. The aetiological agents of both diseases, two Treponema pallidum subspecies, are genetically similar. This study aimed to assess the prevalence of these treponematoses and the occurrence of pathogens causing similar skin lesions in the Ashanti region of Ghana. A point-of-care test was used to determine the seroprevalence of the treponematoses. Both yaws and syphilis were identified in the Ashanti region of Ghana. Multiplex PCR was used to identify treponemes and other pathogens that cause similar skin lesions. The results indicated that the seroprevalences of T. pallidum in individuals with yaws-like and syphilis-like lesions were 17.2% and 10.8%, respectively. Multiplex PCR results showed that 9.1%, 1.8% and 0.9% of yaws-like lesions were positive for Haemophilus ducreyi, herpes simplex virus-1 (HSV-1) and T. pallidum respectively. Among syphilis-like lesions, 28.3% were positive for herpes simplex virus -2 (HSV-2) by PCR. To our knowledge, this is the first time HSV-I and HSV-2 have been reported from yaws-like and syphilis-like lesions, respectively, in Ghana. The presence of other organisms apart from T. pallidum in yaws-like and syphilis-like lesions could impede the total healing of these lesions and the full recovery of patients. This may complicate efforts to achieve yaws eradication by 2030 and the elimination of syphilis and warrants updated empirical treatment guidelines for skin ulcer diseases.


Assuntos
Haemophilus ducreyi , Sífilis , Treponema pallidum , Bouba , Humanos , Gana/epidemiologia , Bouba/epidemiologia , Bouba/microbiologia , Sífilis/epidemiologia , Sífilis/microbiologia , Feminino , Adulto , Masculino , Haemophilus ducreyi/isolamento & purificação , Haemophilus ducreyi/genética , Adolescente , Prevalência , Treponema pallidum/genética , Treponema pallidum/isolamento & purificação , Criança , Adulto Jovem , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/isolamento & purificação , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Pele/microbiologia , Pele/patologia , Pele/virologia , Pré-Escolar , Infecções por Treponema/epidemiologia , Infecções por Treponema/microbiologia
2.
Heliyon ; 10(3): e25493, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38356605

RESUMO

In Africa, indigenous fermented condiments contribute to food security as a low-cost source of protein. Okpeye is an indigenous fermented condiment produced from Prosopis africana seeds. The reliance on spontaneous fermentation processes and unhygienic practices during production often results in the contamination of the final product with microbial hazards. A microbiological evaluation of 18 commercial samples of okpeye purchased from six markets in two cities in southeastern Nigeria was conducted. Fifty-nine (59) bacteria were isolated and identified at the species level by phenotyping and sequencing the 16S rRNA, gyrB and rpoB genes. Bacillus (47.4 %) and Staphylococcus (42.3 %) were the predominant bacterial genera in okpeye. Overall, B. amyloliquefaciens and S. simulans were the most frequently occurring bacteria and were present in all samples. In addition, B. cereus was isolated in samples obtained from all markets. Other bacterial species included B. velezensis, Oceanobacillus caeni, S. cohnii, Escherichia fergusonni and Vagacoccus lutrae. The B. cereus isolates (10) were screened for the presence of 8 enterotoxin genes (hblA, hblC, hblD, nheA, nheB, nheC, cytK, entFM) and one emetic gene (cesB). The non-haemolytic enterotoxin (nheABC) and haemolytic enterotoxin (hblABD) complexes were present in 70 % and 50 % of B. cereus respectively. The positive rate of cytK and entFM genes was 70 %, while the cesB gene was 30 %. Antibiotic susceptibility assessment showed that most of the isolates were susceptible to gentamicin, tetracycline, streptomycin, and erythromycin but resistant to ciprofloxacin and vancomycin. These findings highlight the need for further controls to reduce contamination with potential pathogenic bacteria in indigenous fermented condiments such as okpeye. There is also a need to educate producers regarding hygienic practices to safeguard public health and food security.

3.
Antibiotics (Basel) ; 12(5)2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37237746

RESUMO

BACKGROUND: Antimicrobial resistance (AMR) is one of the biggest threats to public health. The food chain has been recognised as a vehicle for transmitting AMR bacteria. However, information about resistant strains isolated from African traditional fermented foods remains limited. Nono is a traditional, naturally fermented milk product consumed by many pastoral communities across West Africa. The main aim of this study was to investigate and determine the AMR patterns of lactic acid bacteria (LAB) involved in the traditional fermentation of milk for Nono production, and the presence of transferable AMR determinants. METHODS: One hundred (100) LAB isolates from Nono identified in a previous study as Limosilactobacillus fermentum, Lactobacillus delbrueckii, Streptococcus thermophilus, Streptococcus infantarius, Lentilactobacillus senioris, Leuconostoc pseudomesenteriodes, and Enterococcus thailandicus were investigated. The minimum inhibitory concentration (MIC) was determined for 18 antimicrobials using the micro-broth dilution method. In addition, LAB isolates were screened for 28 antimicrobial resistance genes using PCR. The ability of LAB isolates to transfer tetracycline and streptomycin resistance genes to Enterococcus faecalis was also investigated. RESULTS: The experiments revealed variable antimicrobial susceptibility according to the LAB isolate and the antimicrobial tested. The tetracycline resistance genes tet(S) and tet(M) were detected in isolates Ent. thailandicus 52 and S. infantarius 10. Additionally, aad(E) encoding resistance to streptomycin was detected in Ent. thailandicus 52. The conjugation experiments suggested that the tet(S) and aad(E) genes were transferable in vitro from isolate Ent. thailandicus 52 to Ent. faecalis JH2-2. SIGNIFICANCE AND IMPACT: Traditional fermented foods play a significant role in the diet of millions of people in Africa, yet their contribution to the burden of AMR is largely unknown. This study highlights that LAB involved in traditionally fermented foods could be potential reservoirs of AMR. It also underscores the relevant safety issues of Ent. thailandicus 52 and S. infantarius 10 for use as starter cultures as they carry transferable AMR genes. Starter cultures are an essential aspect of improving the safety and quality attributes of African fermented foods. However, AMR monitoring is an important safety aspect in the selection of starter cultures for improving traditional fermentation technologies.

4.
Microb Cell ; 9(5): 123-125, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35647177

RESUMO

Unlike other heterotrophic bacteria, Mycobacterium tuberculosis (Mtb) can co-catabolize a range of carbon sources simultaneously. Evolution of Mtb within host nutrient environment allows Mtb to consume the host's fatty acids as a main carbon source during infection. The fatty acid-induced metabolic advantage greatly contributes to Mtb's pathogenicity and virulence. Thus, the identification of key enzymes involved in Mtb's fatty acid metabolism is urgently needed to aid new drug development. Two fatty acid metabolism enzymes, phosphoenolpyruvate carboxykinase (PEPCK) and isocitrate lyase (ICL) have been intensively studied as promising drug targets, but recently, Quinonez et al. (mBio, doi: 10.1128/mbio.03559-21) highlighted a link between the fatty acid-induced dormancy-like state and drug tolerance. Using metabolomics profiling of a PEPCK-deficient mutant, Quinonez et al. identified that over-accumulation of methylcitrate cycle (MCC) intermediates are phenotypically associated with enhanced drug tolerance against first- and second- line TB antibiotics. This finding was further corroborated by metabolomics and phenotypic characterization of Mtb mutants lacking either ICL or 2-methylcitrate dehydratase. Fatty acid metabolism induced drug-tolerance was also recapitulated in wildtype Mtb after treatment with authentic 2-methylisocitrate, an MCC intermediate. Together, the fatty acid-induced dormancy-like state and drug tolerance are attributed to dysregulated MCC activity.

5.
Trop Med Health ; 49(1): 102, 2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-34965891

RESUMO

Globally, the prevailing COVID-19 pandemic has caused unprecedented clinical and public health concerns with increasing morbidity and mortality. Unfortunately, the burden of COVID-19 in Africa has been further exacerbated by the simultaneous epidemics of Ebola virus disease (EVD) and Lassa Fever (LF) which has created a huge burden on African healthcare systems. As Africa struggles to contain the spread of the second (and third) waves of the COVID-19 pandemic, the number of reported cases of LF is also increasing, and recently, new outbreaks of EVD. Before the pandemic, many of Africa's frail healthcare systems were already overburdened due to resource limitations in staffing and infrastructure, and also, multiple endemic tropical diseases. However, the shared epidemiological and pathophysiological features of COVID-19, EVD and LF as well their simultaneous occurrence in Africa may result in misdiagnosis at the onset of infection, an increased possibility of co-infection, and rapid and silent community spread of the virus(es). Other challenges include high population mobility across porous borders, risk of human-to-animal transmission and reverse zoonotic spread, and other public health concerns. This review highlights some major clinical and public health challenges toward responses to the COVID-19 pandemic amidst the deuce-ace of recurrent LF and EVD epidemics in Africa. Applying the One Health approach in infectious disease surveillance and preparedness is essential in mitigating emerging and re-emerging (co-)epidemics in Africa and beyond.

6.
Braz J Microbiol ; 52(2): 869-881, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33694058

RESUMO

The aim of this research was to identify the key lactic acid bacteria associated with the fermentation of dairy traditional fermented products for developing starter cultures for controlled fermentation. A total of 100 lactic acid bacteria (LAB) were isolated from dairy traditional fermented products. Samples were obtained from eight producers in the South East of Nigeria. Isolates were identified by phenotypic and genotypic techniques including rep-PCR genotyping and sequencing of the 16S rRNA, pheS and rpoA genes. Isolates were characterised for antimicrobial activity against foodborne pathogens, exopolysaccharide (EPS) production and survival at low pH and in the presence of bile salts. All isolates clustered into 11 distinct rep-PCR groups and were identified as Lactobacillus fermentum (40%), Lactobacillus delbrueckii (23%), Streptococcus thermophilus (22%), Streptococcus infantarius (10%), Lactobacillus senioris (2%), Leuconostoc pseudomesenteriodes (2%) and Enterococcus thailandicus (1%). Lactobacillus fermentum showed a broad spectrum antimicrobial activity and survival at low pH, while Lactobacillus delbrueckii was able to tolerate low pH and produce EPS. All isolates survived in vitro exposure to 1% (w/v) bile salts over a 3-h period. L. fermentum, L. delbrueckii and S. thermophilus could be used to simulate the fermentation of dairy traditional fermented products.


Assuntos
Produtos Fermentados do Leite/microbiologia , Lactobacillales/isolamento & purificação , Lactobacillales/fisiologia , Antibiose , Ácidos e Sais Biliares/farmacologia , Fermentação , Genes Bacterianos/genética , Genótipo , Concentração de Íons de Hidrogênio , Lactobacillales/classificação , Lactobacillales/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Nigéria , Polissacarídeos Bacterianos/metabolismo , RNA Ribossômico 16S/genética
8.
Int J Food Microbiol ; 311: 108356, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31670141

RESUMO

Different samples of three products including Bikalga and Soumbala from Burkina Faso (West Africa) and Ntoba Mbodi from Congo-Brazzaville (Central Africa) were evaluated. The bacteria (400) were phenotyped and genotypically characterized by Rep-PCR, PFGE, 16S rRNA and rpoB gene sequencing and spa typing. Their PFGE profiles were compared with those of 12,000 isolates in the Center for Disease Control (CDC, USA) database. They were screened for the production of enterotoxins, susceptibility to 19 antimicrobials, presence of 12 staphylococcal toxin and 38 AMR genes and the ability to transfer erythromycin and tetracycline resistance genes to Enterococcus faecalis JH2-2. Fifteen coagulase negative (CoNS) and positive (CoPS) species characterized by 25 Rep-PCR/PFGE clusters were identified: Staphylococcus arlettae, S. aureus, S. cohnii, S. epidermidis, S. gallinarum, S. haemolyticus, S. hominis, S. pasteuri, S. condimenti, S. piscifermentans, S. saprophyticus, S. sciuri, S. simulans, S. warneri and Macrococcus caseolyticus. Five species were specific to Soumbala, four to Bikalga and four to Ntoba Mbodi. Two clusters of S. gallinarum and three of S. sciuri were particular to Burkina Faso. The S. aureus isolates exhibited a spa type t355 and their PFGE profiles did not match any in the CDC database. Bacteria from the same cluster displayed similar AMR and toxin phenotypes and genotypes, whereas clusters peculiar to a product or a location generated distinct profiles. The toxin genes screened were not detected and the bacteria did not produce the staphylococcal enterotoxins A, B, C and D. AMR genes including blazA, cat501, dfr(A), dfr(G), mecA, mecA1, msr(A) and tet(K) were identified in CoNS and CoPS. Conjugation experiments produced JH2-2 isolates that acquired resistance to erythromycin and tetracycline, but no gene transfer was revealed by PCR. The investigation of the heterogeneity of Staphylococcus species from alkaline fermented foods, their relationship with clinical and environmental isolates and their safety in relation to antimicrobial resistance (AMR) and toxin production is anticipated to contribute to determining the importance of staphylococci in alkaline fermented foods, especially in relation to the safety of the consumers.


Assuntos
Enterotoxinas/genética , Alimentos Fermentados/microbiologia , Staphylococcus , Antibacterianos/farmacologia , Burkina Faso , Coagulase/genética , Congo , RNA Polimerases Dirigidas por DNA/genética , Farmacorresistência Bacteriana/genética , Eritromicina/farmacologia , Genótipo , Testes de Sensibilidade Microbiana , Fenótipo , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Staphylococcus/classificação , Staphylococcus/efeitos dos fármacos , Staphylococcus/genética , Staphylococcus/isolamento & purificação , Tetraciclina/farmacologia
9.
Food Microbiol ; 66: 165-172, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28576365

RESUMO

This study investigated the influence of the addition of soy products on the microbiology, nutritional and physico-chemical characteristics of garri, a fermented cassava product. Malted soy flour (MSF) and soy protein (SP) were separately added (12% w/w) to cassava mash prior to controlled fermentation, while non-supplemented cassava mash served as a control. Identification of lactic acid bacteria (LAB) and aerobic mesophilic bacteria was accomplished by repetitive sequence based (rep)-PCR analysis and 16S rRNA gene sequencing. Physicochemical, nutritional and sensory characterisation of control and soy-fortified garri was performed using conventional methods. rep-PCR allowed differentiation of 142 isolates into 41 groups corresponding to 6 species of LAB and 25 species of aerobic mesophiles. LAB isolates belonged to the genera Lactobacillus, Weissella, Leuconostoc and Lactococcus with Leuconostoc mesenteroides being the dominant species in control and MSF-cassava while Weissella cibaria dominated SP-cassava fermentation. Aerobic mesophiles included Gram positive and negative bacteria including species of the genera Bacillus, Clostridium, Staphylococcus, Serratia, Acinetobacter and Raoultella. Diversity of aerobic mesophiles varied between control, MSF- and SP- cassava mash. Protein content of soy-fortified garri increased from 0.73% to 10.17% and 10.05% in MSF and SP garri respectively with a significant decrease in total cyanide from 26 to 11 ppm. Results from physicochemical and organoleptic evaluation indicate that supplementation of cassava with soy products prior to fermentation can produce acceptable garri. Soy products can be considered a viable option for protein fortification of garri, a low protein food with the aim of combating malnutrition.


Assuntos
Bactérias/metabolismo , Aditivos Alimentares/análise , Alimentos Fortificados/análise , Manihot/microbiologia , Proteínas de Soja/análise , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Fermentação , Microbiologia de Alimentos , Alimentos Fortificados/microbiologia , Manihot/química , Manihot/metabolismo
10.
Int J Syst Evol Microbiol ; 65(11): 4256-4262, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26333923

RESUMO

Investigation of the microbial diversity of Ntoba Mbodi, an African food made from the alkaline fermentation of cassava leaves, revealed the presence of a Gram-positive, catalase-positive, aerobic, motile and rod-shaped endospore-forming bacterium (NM73) with unusual phenotypic and genotypic characteristics. The analysis of the 16S rRNA gene sequence revealed that the isolate was most closely related to Lysinibacillus meyeri WS 4626T (98.93%), Lysinibacillus xylanilyticus XDB9T (96.95%) and Lysinibacillus odysseyi 34hs-1T (96.94%). The DNA-DNA relatedness of the isolate with L. meyeri LMG 26643T, L. xylanilyticus DSM 23493T and L. odysseyi DSM 18869T was 41%, 16% and 15%, respectively. The internal transcribed spacer-PCR profile of the isolate was different from those of closely related bacteria. The cell-wall peptidoglycan type was A4α, L-Lys-D-Asp and the major fatty acids were iso-C15:0, anteiso-C15:0, anteiso-C17:0 and iso-C17:0 and iso-C17:1ω10c. The polar lipids included phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphoaminolipid, aminolipid, two phospholipids and two unknown lipids. The predominant menaquinones were MK-7 and MK-6. Ribose was the only whole-cell sugar detected. The DNA G+C content was 38 mol%. Based on the results of the phenotypic and genotypic characterization, it was concluded that the isolate represents a novel species of the genus Lysinibacillus, for which the name of Lysinibacillus louembei sp. nov. is proposed. NM73T ( = DSM 25583T = LMG 26837T) represents the type strain.


Assuntos
Bacillaceae/classificação , Microbiologia de Alimentos , Manihot/microbiologia , Filogenia , Folhas de Planta/microbiologia , Bacillaceae/genética , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , Congo , DNA Bacteriano/genética , Ácidos Graxos/química , Fermentação , Dados de Sequência Molecular , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
11.
Int J Syst Evol Microbiol ; 65(10): 3576-3579, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26297247

RESUMO

Investigation of the microbial diversity of Bandji, a traditional palm wine from Burkina Faso (West Africa) revealed the presence of two yeast isolates (YAV16 and YAV17T) with unusual phenotypic and genotypic characteristics. The isolates divide by bipolar budding with no production of ascospores. Phylogenetic analysis of concatenated sequences of the 26S rRNA gene D1/D2 and internal transcribed spacer (ITS) regions indicated that the novel species was most closely related to Kloeckera lindneri and Hanseniaspora valbyensis. The new isolates differed from K. lindneri NRRL Y-17531T and H. valbyensis CBS 479T by substitutions in the D1/D2 region of 12 and 16 nt respectively. The divergence in the ITS region from the closely related species was characterized by substitutions of 45-46 nt. Repetitive palindromic PCR (rep-PCR) profiles of YAV16 and YAV17T were also significantly different from those of K. lindneri MUCL 31146T ( = NRRL Y-17531T), H. valbyensis NCYC 17T ( = CBS 479T) and other species of the genus Hanseniaspora. Based on the results of the phenotypic and genotypic characterizations, it was concluded that the new isolates represent a novel species for which the name Hanseniaspora jakobsenii sp. nov. is proposed with YAV17T ( = CBS 12942T = DSM 26339T = NCYC 3828T; MycoBank number MB 805785) as the type strain.


Assuntos
Arecaceae/microbiologia , Hanseniaspora/classificação , Filogenia , Vinho/microbiologia , Burkina Faso , DNA Fúngico/genética , Genótipo , Hanseniaspora/genética , Hanseniaspora/isolamento & purificação , Dados de Sequência Molecular , Técnicas de Tipagem Micológica , RNA Ribossômico/genética , Análise de Sequência de DNA
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